Wagon unloader



Dec. 4, 1956 E. K. HANSEN 2,772,796 I WAGON UNLOADER Filed May 2'7. 1955 g 5 Sheets-Sheet 1 fig. 1

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w; 1' l y I45 2? I" Q 52 (Hul INVENTOR. ELMEP K. HANSEN BY WzgM 4 TTORNEK E. K. HANSEN WAGON UNLOADER Dec. 4, 1956 5 Sheets-Sheet 2 Filed May 27. 1955 /NVENTO/2 ,47'7'O/PNEL ELMEI? K HAN$ON B) E. K. HANSEN WAGON. UNLOADER Dec. 4, 1956 7 5 Sheets-Sheet 3 Filed May 27. 1955 V Wm M ww P m4 /m N .7 K K Dec. 4, 1956 E. K. HANSEN WAGON UNLOADER Filed May 27. 1.955

5 Sheets-Sheet 4 INVENTOR. EL MER K HA'NJEN ATTO/PNEK Dec 4, 1956 E. HANSEN WAGON UNLOADER Filed May 27. 1955 5 Sheets-Sheet 5 IN VEN TOR. EL MEFP K. H4 N5 EN BY 14 TTO/PNEY.

United States Patent Office 7 Patented Dec. 4, 1956 WAGON UNLOADER Elmer K. Hansen, Sioux City, Iowa Application May 27, 1955, Serial No. 511,484

7 Claims. (Cl. 2148;3.14)

This invention relates generally to material handling apparatus and more particularly to a wagon unloader.

An object of this invention, therefore, is to provide an improved wagon unloader.

A further object of this invention is to provide a wagon unloader having rotatable flipper or paddle units which operate to discharge material from the wagon at a uniform rate.

Another object of this invention is to provide a wagon unloader in which material in the wagon is moved at a slowly increasing rate of speed to a series of discharge flippers to avoid any sudden load of material on the flippers.

A further object of this invention is to provide a clutch assembly for a conveyor which automatically prevents any fast starting or stopping of the conveyor to thus avoid any overloading of the conveyor.

Another object of this invention is to provide a wagon unloader which is simple in construction, economical to manufacture and efficient in operation to readily unload.

material at a uniform rate from a moving or stationary wagon.

Further objects, features and advantages of this invention Will become apparent from a consideration of the following description when taken in connection with the accompanying drawing in which:

Fig. 1 is a longitudinal sectional view of the wagon unloader of this invention shown in assembly relation 'with a wagon;

Fig. 2 is a reduced perspective view of the wagon unloader and wagon shown in Fig. 1;

Fig. 3 is an enlarged fragmentary perspective view of the clutch assembly for the wagon unloader of this invention, showing the assembly in an inoperative or no load position;

Fig. 4 is an enlarged fragmentary perspective view of :the clutch assembly, illustrated similarly to Fig. 3, showing the clutch assembly in amoved position therefor corresponding to a full load position; q

Fig. 5 is a diagrammatic top plan view of a portion :of the clutch assembly in the position therefor illustrated :in Fig. 3;

Fig. 6 is 'a diagrammatic top plan view of the clutch assembly, illustrated similarly to Fig. 5, and showing the assembly in the position illustrated in Fig. 4;

Fig. 7 is a fragmentary side elevational ,view of a portion of the wagon unloader-of 'thisinvention, showing the flipper operating mechanism therefor, with some parts broken awayand other parts shown in section for thepurpose of clarity;

Fig. 8 is a fragmentary enlarged side elevational view of a portion of the flipper operating mechanism shownately prior to operation of the mechanism to drive the flippers;

Figs. 10 and 11 are sectional views looking along the lines 10-10 and 11-11 in Figs. 8 and 9, respectively.

Fig. 12 is a fragmentary front elevational view of the wagon unloader of this invention; and

Fig. 13 is a diagrammatic view of a portion of the wagon unloader of this invention.

With reference to the drawing, the wagon unloader of this invention, indicated generally at 10, is illustrated in Figs. 1 and 2 in assembly relation with a wagon 11 having a pair of ground wheels 12.' The unloader 10 and the wagon 11 are adapted to be towed by a tractor (not shown) having a power take off connected to a drive shaft 14 at the forward end 16 of the wagon 11 for driving the unloader 10.

As best appears in Figs. 1 and 2, the unloader 10 includes a bed conveyor 17 arranged adjacent the bottom wall 18 of the wagon 11, and a discharge mechanism, indicated generally at 19, removably mounted on the front end 16 of the wagon 11.

The discharge mechanism 19 discharges material from the wagon 11 to a conveyor 22 extended transversely of the wagon 11 at the front end 16 thereof. A vertically swingable elevator or conveyor 25, communicating with the transverse conveyor 22, is provided for delivering the material into feed bunks or the like during travel of the wagon 11.

The discharge mechanism The discharge mechanism 19 includes a series of five horizontally extended vertically spaced flipper or paddle units 23 arranged forwardly of the wagon front end 16. Each unit 23' includes a horizontal shaft 24 and a pair of angle members 26 secured to opposite sides of the shaft 24 so. that the angle member legs 27 in each unit 23 are substantially parallel and extend in opposite directions from the shaft 24. The units 23 are arranged within and have their shafts 24 supported on a casing or housing 28 having a downwardly and forwardly inclined front wall 29 for deflecting material thrown forwardly by the flipperunits 23 onto the transverse conveyor 22.

The drive shaft 14 drives the transverse conveyor 22 through a direct connection (not shown) and carries a gear 31 arranged below the wagon 11 in a driving relation with a gear 32 on a drive shaft 33 for a gear reduction unit 34 (Figs. 3 and 4). A driven shaft 36 for the gear reduction unit 34 (Figs. 3, 4 and 7) drives a sprocket wheel 37 arranged below and to one side of the wagon 11 in a counterclockwise direction as viewed in Fig. 7.

A sprocket chain 38, trained about a small idler wheel 39 and the wheel 37, drives a larger power transmitting wheel 41 mounted on a shaft 24a (Fig. 7). The power wheel 41 rotates freely on the shaft 24a whichforms a part of the lowermost flipper unit 23. A sprocket Wheel 42 fixed on the shaft 24a for rotation therewith drives a sprocket chain 43 trained about similar sprocket'wheels 42 secured to the shafts 24 for the other flipper units 23.-

To provide for rotation of the shaft 24a with the power.

wheel 41 for driving of the wheels 42 when desired, an arm 46 (Figs. 7 and 8) is secured to the shaft 24a at a position outwardly of the power wheel 41. A spacer sleeve 47, on the shaft 2471 between the power wheel 41 and the arm 46, maintains the arm 46 in an outwardly spaced relation with the wheel 41.

A pair of parallel spaced lever members 48, pivotally supported at 49 on the wagon frame 51 (Figs. 7, 8 and 9) carry a pin 52 extended between the lever members 48. A third lever member 53 rigidly secured to and extended rearwardly from the parallel lever members 48 carries a spring 54 connected to the frame 51 for biasing the lever member 53 to a position corresponding to upright positions for the lever members 48. In this position of the lever members'48, the pin 52 is received in a notch 56 in a the outer or free end 57 of the arm 46.

' It is seen, therefore, that in the upright positions of the lever members 48 in which the pin 52 is received in the notch 56, the arm 46 and the shaft 24a are maintained in stationary positions. On downward movement of the lever 53, in response to a downward pull on a cable 58, the lever members 48 and the pin 52 are moved rearwardly to positions in which the'pin 52 is disengaged from the notch 56 and in a clearance relation with the arm 46 to release the arm 46 for rotation with the power wheel 41. Y

To provide for rotation of the arm 46 with the power wheel 41 on movement of the pin 52 out of the notch 56, an irregularly shaped dog 59 is mounted on the arm 46. The dog 59 carries a shaft 61 extended through the arm 56 and provided on its free end with a half round portion 62 positioned adjacent the power wheel 41.

In the position of the pin 52 within the notch 56, a stop portion 63 on the outer end of the dog 59 engages the pin 52 so that the dog 59 is in the position shown in Fig. 8. On movement of the pin 52 out of the notch 56 to a position in a clearance relation with the dog stop portion 63, a spring 64 extended between a collar 66 on the shaft 24a and the dog 59 rotates the dog 59 in a counterclockwise direction as viewed in Fig. 8 to a stop position shown in Fig. 9 in which the dog 59 is engaged with a stop bolt 67 extended through the arm 46. A washer 68 on the bolt 67 maintains the dog 59 against move ment outwardly of the arm 46 to thus maintain the half roundportion 62 adjacent the power wheel 41.

On rotation of the dog 59 to the position illustrated in Fig. 9, the half round portion 62 is rotated to a position extended into the path of a rectangular block 69 (Fig. 11) mounted on the wheel 41 adjacent the periphery thereof. On engagement of the block 69 with the half round portion 62, the arm 46 and the dog 59 rotate in a counterclockwise direction as viewed in Figs. 8 and 9 with the power wheel 41.

Since the block 69 has a tendency to wear at a-corner as a result of the engagement of such corner with the half round portion 62, the block 69 is removably mounted on the wheel 41, by means of screws 71. As a result, when'one corner of the block 69 has worn, the block 69 is removed and re-positioned on the wheel 41 for engagement of an ,unworn corner with the half round portion 62.

It is seen, therefore, that on forward movement of the lever members 48, in response to a downwardpull on the cable 58, the arm .46 isrotatable with the power wheel 41. Asa result, the shaft 24:: is rotated to in turn rotate the drive wheels 42 for the flipper units 23. On release of the downward pull on the cable 58, the spring 54 returns the lever members 48 totheir upright positions illustrated in Fig. 87 The pin 52 ridesf downwardly on the cam shape surface 72 at the free end 57 of the arm 46 into engagement with the stop portion 63 on the dog .59. The pin 52 then moves into thenotch 56in the arni 46 to hold 7 the arm 46 against'rotation with the'wheel' 41. The dog 59 is rotated by the pin '52 in a clockwise direction, as viewed in Fig. 9, to move the dog 59 into the position shown in ,Fig. 8 corresponding toa position in which the half round portion 62 is in a clearance relation with the block '69 (Fig.

It is seen, therefore, that in the Fig. 9 position of the lever 53, the power wheel 41 operates to drive the flipper units 23. In the Fig. 8 position of the lever 53, the shaft 24a is maintained in a stationary position to thus maintain the flipper units 23 in stationary positions corresponding to the position of the units 23 shown in Fig. 1. It is to be noted also that on movement of the lever 53 from the Fig. 9 position to the Fig. 8 position therefor, the flipper units 23 come to rest in the same position, namely, the position shown in Fig. 1. In this position of the flipper units 23, they cooperate to'form a gate to prevent any passage of material from the wagon 11 forwardly into the casing 28.

The clutch assembly To provide for a gradual starting and stopping of the bed conveyor 17 which delivers the material to the flipper units 23, a clutch assembly, indicated generally at 81 (Figs. 3 and 4) is provided on the underside of the wagon 11 for transmitting power from the drive shaft 14 t0 the driven shaft 82 (Fig. 1) of the bed conveyor 17. The assembly 81 includes a first pulley 83 on the shaft'33 and a second pulley 84 connected to a drive shaft 86 for a gear reduction unit 87 which drives the bed conveyor shaft 82 by means of a connecting mechanism (not shown).

A pair of variable speed pulleys 88 and 89, of well known type, having a common movable intermediate member 91 (Figs. 5 and 6) are mounted on a shaft 92 extended longitudinally of the wagon 11. The shaft 92 is carried on the lower ends of a pair of downwardly extended arms 93 (Figs. 3, 4, 5 and 6) carried on a pin 94 extended longitudinally of the wagon and supported on a pair of wagon frame members, one of which is indicated at 96. The arms 93 are swingable transversely of the wagon to move the variable speed pulleys 88 and 89 in directions toward and away from the stationary pulleys 83 and 84. A first belt 97is extended about the stationary pulley 83 and the variable speed pulley 88 for driving the pulley 88 in response to rotation of the pulley 83. A second belt 88 extends about the variable speed pulley 89,and the stationary pulley 84 for driving the pulley 84 fromthe pulley 89.

It is seen, therefore, that upon swinging movement of the variable speed pulleys 88 and'89 about the pin 94, in a direction toward the stationary pulley 84, the first belt 97 is tightened and moved inwardly on the pulley 88 to in turn increase the speed thereof and move the intermediatepulley member 91 in a direction to move the belt 98 outwardly on the pulley 89 to thereby increase the speed of rotation of the belt 98 and the pulley 84. As a result, the speed of the shaft 86 for the pulley 84 is increased to in turn increase the speed of the bed conveyor 17 to deliver material at a faster rate to the discharge mechanism 19.

To swing the variable speed pulleys 88 and 89 .about the pin 94, a pulley or disc 99, arranged between the stationary pulley 83 and the variable speed pulley 88 is rotatably mounted on a shaft ltll .carried by a downwardly projected support plate 102 carried by the wagon frame member 96. Pivotally connected at 103 to the disc 99, is a .rod 104which is secured to and projected axially through a tube member 106 (Figs. 3 and 4). A larger tube 107 mounted about the tube v106 is clamped by a bolt 108 to one end of a strap 109. The opposite end of the strap .109 is mounted about the shaft 92 for the variablespeed pulleys 88 and 89.

A plate 112, loosely-received onthe r0d 104, andar ranged in abutting engagement with'the end 113 of the tube 106 is connected by a;pair of springs 11410 a similar plate .116 loosely received on the, rod 104'in abutting engagement with the end 117 of the tube 107. (Thus, any movement of the tube 106 outwardly of the tube 107, as illustrated in Fig. 4, isresisted ;by the springs 114.

An arm 118 secured atone of its ends 119 to the shaft 92 for the variable speedpulleys- 88 and 89, has a laterally olfset'opposite end portion 121 which carries a first notches 146.

roller 122 ridable on the inside of the belt 97. A bar 123 secured to the arm end portion 121 has a laterally projected free end portion 124 positioned against the outer side of the belt 97 at a location opposite the roller 122.

It is seen, therefore, that in the Fig. 3 position of the variable speed pulleys88 and 89, corresponding to an off or non-operating condition of the bed conveyor 17, the bar 123 operates to hold the belt 97 out of direct riding contact on the first pulley 83. As a result, no burning of the belt 97 and no driving of the variable speed pulley 88 occurs on rotation of the pulley 83 in the Fig. 3 position of the assembly 81. It is apparent that the pulley 83 is in motion at all times during driving of the drive shaft 14. On swinging movement of the variable speed pulleys 88 and 89 to the positions shown in Fig. 4, corresponding to a full speed operation of the bed conveyor 17, the roller 122 is swung downwardly in contact with the belt 97 to further tighten the belt 97 on the pulleys 83 and 88.

A downwardly and outwardly extended strap member 126 (Figs. 3 and 4) secured to the end 119 of the arm 118 carries a spring 127 connected to the wagon frame member 96 for biasing the strap 127 in an upward direction. The spring 127 facilitates swinging movement of the variable speed pulleys 88 and 89 toward the stationary pulley 84.

An elongated lever member 128 pivotally connected at 129 to the strap 126 is guided by a downwardly ex tended member 131 on the arm 118 into engagement with the inclinded intermediate portion 132 of the arm 118 on upward swinging movement of the lever 128 about the pivot 129. A link 133 pivotally connected to and extended between the disc 99 and the free end of the lever 12? moves the lever 128 upwardly during clockwise roration of the disc 99 as viewed in Fig. 4. As a result, on movement of the disc 99 to the position shown in Fig. 3, the lever 128 moves the arm 118 upwardly to a position in which the bar 123 holds the belt 97 ofi the pulley 83.

For moving the disc 99 between the positions illustrated in Figs. 3 and 4, a cable 136 is secured to and extended about the disc 99. The cable 136 is trained about a pulley'137 arranged below the wagon 11 at a position above the pulley 84 and a pair of pulleys 138 and 139 (Fig. 12) arranged on the front end 21 of the unloader casing 28. Other pulleys (not shown) between the pulleys 137 and 138 direct the cable 136'onto the horizontal pulley 138 and the upright pulley 137.

Intermediate the pulleys 137 and 138, the cable 136 has its ends secured to a lever 141 (Fig. 12) carried on a segment 143 mounted at a central position on the front side of the unloader casing 28. The lever 141 is swingable about its pivotal connection 142 with the segment 143 between the dotted and full line positions shown in Fig. 12. A spring pressed rod 144 movably mounted on the lever 141. cooperates with notches 146 on the segment 143 to maintain the lever 141 in an intermediate position between the dotted and full line positions illustrated in Fig. 12.

It is seen, therefore, that swinging movement of the lever 141 operates to move the cable 136 to rotate, the disc 99. In the full line position of the lever 141 (Fig. 12) the bed conveyor 17 is in an off or rest condition. in the dotted line position of the lever 141, the bed conveyor 12 is in a full speed condition.

Operation Assume that the wagon 11 is loaded with silage, grain or the like. to be unloaded and that the drive shaft 14 is connected to a tractor power take off (not shown). At the desired point of unloading, the lever 141 is swung in a counterclockwise direction as viewed in Fig. 12 to a position in which the rod 144 is engaged in one of the In response to such movement of the lever 141, the disc 99 is rotated in a counterclockwisedirection as viewed in Fig. 3 to inturn move the free end 151 of a bracket member 152 seciiredto the disc 99 toward the right. A strap 153, pivotally con-- nected at 154 to the free end 151 of the bracket 152, is in turn moved to the right to thereby exert a pull on the cable 58 secured to the strap 153. Such pull on the cable 58 is sufficient to move the lever 53 (Figs. 7, 8 and 9) downwardly to a position moving the pin 52 out of the notch 56 in the arm 46 (Fig. 9). The pin 52 is then in a clearance relation with the arm 46 and the dog 59 to provide for rotation of the shaft 24a with the power wheel 41 to in turn rotate the flipper units 23.

This initial movement of the lever 141 is sufficient to rotate the disc 99 counterclockwise as viewed in Fig. 3 to a position at or slightly past a dead center position of the pivot 103 for the rod 104. As a result, since the pivot 183 has not been moved to the right as viewed in Fig. 3, the variable speed pulley 88 has not been moved in a direction to tighten the belt 97. Conse 'quently, for an initial movement of the lever 141, the

operation of the bed conveyor 17 is not started.

On further movement of the lever 141 to the left as viewed in Fig. 12, the disc 99 is rotated in a counterclockwise direction as viewed in Fig. 3 to move the rod pivot 103 to the right to in turn move the rod 104 to the right to thus swing the variable speed pulley 88 in a direction away from the stationary pulley 83. The roller 122 is moved downwardly to cooperate with the pulley 88 to tighten the belt 97 about the pulleys 83 and 88. As a result, power is transmitted by the belt 97 from the pulley 83 to the variable speed pulley 88 which in turn drives the variable speed pulley 89 to drive the pulley 84. The bed conveyor 17 then moves forwardly at a slow rate of speed.

It is apparent that as the pulley 88 is progressively moved toward the right as viewed in Fig. 3, in response to movement of the lever 141 toward the dotted line position therefor shown in Fig. 12, the belt 97 is progressively tightened about the pulley 88 to move the belt 97 inwardly on the pulley 88 to thereby increase the speed of the pulley 88. As the speed of the pulley 88 is increased, the speed of the pulley 89 is correspondingly increased and in addition the belt98 is moved outwardly on the pulley 89 to further increase the speed of the pulley 84. As a result, in response to movement of the lever 141 toward the left as viewed in Fig. 12, the,

speed of the bed conveyor 17 is progressively increased. During normal operation of the unloader 10 the speed of the bed conveyor 17 is progressively increased to the desired speed during an unloading operation.

As the material is moved forwardly of the wagon 11 by the bed conveyor 17, such material is progressively moved into contact with the flipper units 23 which act independently to impel or throw the material forwardly against the casing wall 29 and onto the transverse conveyor 22 which operates to discharge the material onto the conveyor 23 and thence to the feed bunks or the like. As best appears in Fig. l, in the inoperativeposition of the flipper units 23, a gate member 161 extends between the bed conveyor 17 and the lowest flipper unit23. The gate 161 thus acts to positively prevent any flow of material outwardly of the wagon 11 between the lowest flipper unit 23 and the bed conveyor 17. The arrangement of the flipper units 23 prevents any flow of material outwardly of the wagon 11 between the units 23.

The gate 161 is mounted on a shaft 162 (Figs. 1 and 13) extended outwardly of the unloader casing 28 and provided with a radially extended pin 163 arranged between the casing 28 and the gear reduction unit'87 (Fig.1). 1 An upwardly extended dog 164 (Fig. 13) clamped to the cable 136 engages the pin 163 during movement of the lever 141 from the dotted line position to the full line position shown in Fig. 12 to swing the gate 161 in a counterclockwise direction as viewed in Fig. 13 to an upright position.

During initial movement of the lever 141' to operate I the flipper units 23, the dog 164 is moved rearwardly to a position in'a clearance relation with the pin 163. The weight of the gate 161 provides for a downward movement thereof to the dotted line position shown in Fig. 1 permitting forward flow of material from the wagon 11 between the bed conveyor 17 and the lowest flipper unit 23.

To shut off the unloader when the unloading operation has been completed, the lever 141 is moved from the dotted line position to the full line position shown in Fig. 12. In response to such movement, the disc 99 is moved in a clockwise direction from the position shown in Fig. 4 to the position shown in Fig. 3. It is apparent that during such movement the belt 97 is progressively loosened to provide for a progressively decreasing speed of the bed conveyor 17. During final travel of the disc 99, the lever 128 engages the inclined portion 132 of the roller supporting arm 118 to move the roller 122 upwardly to the position illustrated in Fig. 3. In this position of the roller 122, the bar 123 carried thereby acts to hold the belt in a position off the drive pulley 83. As a result, no power is transmitted during the time the drive shaft 14 rotates and the operating lever 141 is in the off position shown in full lines in Fig. 12.

Also, during final travel of the disc 99 to the position shown in Fig. 3, the pull on the cable 58 is released to provide for upward movement of the lever 53 in response to the action of the spring 54. The pin 52 is moved to a position to intercept travel of the arm 46 and dog 59 to thus stop further rotation of the flipper units 23.

From the above description, it is seen that this invention provides a wagon unloader 10 which is readily operable to unload material at a uniform rate. By virtue of the clutch assembly 81, the flow of material from the wagon 11 is automatically started and stopped at a slow speed to prevent any overloading of the bed conveyor 17 for the unloader 10. Further, the flipper units 23 and the gate 161 are automatically moved to the position shown in Fig. 1 when the operation of the unloader 10 is stopped. The flipper units 23 and the gate 161 thus cooperate to function as an end gate to prevent accidental unloading of material from the wagon 11.

Although the invention has been described with respect to a preferred embodiment thereof, it is to be understood that it is not to be so limited, since changes can be made therein which are within the full intended scope of this invention as defined by the appended claims.

I claim:

1. A material unloading device for a container having a bottom wall and side walls, said device including a plurality of substantially horizontal vertically aligned shafts extended across one end of said container, flipper members carried by said shafts, a conveyor mounted in said container adjacent said bottom wall for delivering material to said flipper members, power means for rotating said shafts and moving said conveyor, and clutch means operatively associated with said power means and said conveyor operable to transmit variable power to said conveyor only during rotation of said shafts.

2. For use with a wagon having an open end and means for moving material therein toward said open end, a discharge mechanism removably mounted on said wagon at said open end, said mechanism including a plurality of substantially horizontal vertically spaced shafts, a pair of flipper members of a plate form secured to and extended in opposite directions away from each of said shafts, with said shafts in one position having said flipper members arranged in positions blocking outward travel of material from said wagon end and power means for rotating said shafts such that material in said wagon is engaged and discharged outwardly of said wagon by said flipper members.

3. A material unloading device for a wagon having an open end, movable means in said wagon for. moving material. therein toward said open. end, said device ineluding a conveyor arranged outwardly of said wagon and extended transversely thereof, a plurality of rotatable flipper members extended across said open end for discharging material from saidwagon onto said conveyor, power means for operating said flipper members and said movable means, first clutch means operatively associated with said movable means and said power means and adjustable to provide for varying the speed of said movable means, second clutch means operatively associated with said flippervmembers and said power means, and common control means for said clutch means providing for actuation of said second clutch means to operate said flipper members prior to actuation of said first clutch means to provide for operation of said movable means.

4. A wagon unloader comprising a casing adapted to be mounted at one end of a wagon, vertically spaced flipper units supported on said casing, with each of said units including a shaft and plate members secured to and extended outwardly in opposite directions'from said shaft, power means operable to concurrently rotate said shafts for operation of said flipper units to discharge material from said wagon, with the plate members on adjacent flipper units being relatively arranged for forming an upright obstruction for preventing flow of material out of said wagon in non-rotating positions of said units.

5. For use with a material handling device having a discharge mechanism and conveyor means for delivering material thereto, power means for driving said conveyor means and said discharge mechanism, clutch means comprising a first pulley arranged in a driven relation with said power means, a second pulley arranged in a driving relation with said conveyor means, a shaft movably mounted at a position between said pulleys, a pair of variable speed pulleys on said shaft, a first belt extended about said first pulley and one of said variable speed pulleys, a second belt extended about said second pulley and the other one of said variable speed pulleys, whereby as said shaft is moved toward said second pulley said first vbelt is progressively tightened and said second belt is progressively moved outwardly on the variable speed pulley therefor to progressively increase the speed of rotation of said second pulley, whereby to progressively increase the speed of said conveyor means.

6. A wagon unloader comprising a casing, vertically spaced flipper units supported on said casing, with each of said units including a shaft and a pair of flipper members secured to and extended outwardly in opposite directions from said shaft, power means for rotating said shafts, clutch means operatively associated with said shafts and said power means for selectively transmitting power from said power means to said shafts, with said clutch means providing for the arrangement of said flipper members in upright positions when no power is being transmitted to said shafts.

7. For use with a material handling device which includes means for moving material in one direction, a discharge mechanism positioned so as to receive material from said moving means, said mechanism including a plurality of substantially parallel flipper units, with each of said units including a shaft and a pair of flipper members of a plate form having portions thereof extended outwardly in opposite directions from said shaft, and power means operatively associated with said units for rotating adjacent units in opposite directions.

References Cited in the file of this patent UNITED STATES PATENTS 1,271,906 Juengst July 9, 1918 2,555,558 Peterson June 5, 1951 2,569,191 Peterson et al. Sept. 25, 1951 2,636,400 Recker Apr. 28, 1953 2,676,002 Wolfe Apr. 20, 1954 2,676,721 Hansen Apr. 27, 1954 2,689,484 Phares' Sept. 21, 1954 

